Vestil LDLT series - Manual (Page 18)

18
TROUBLESHOOTING GUIDE - 2-SPEED FOOT PUMP
Before performing any task, always lower the table entirely.
Consult the factory for any problems at time of installation or for any problems not addressed below:
*Check the DC notes page for other troubleshooting notes specific to battery-powered units.
Problem:
1. Platform does not raise when the foot
treadle is pressed. Foot treadle goes
down without excessive force.
2. Platform will fit under no load, but not
when fully loaded. Foot treadle goes
down without excessive force.
3. Platform raises with the pump
downstroke, but lowers with the pump
upstroke.
4. Platform raises, then drifts down.
5. Platform raises, but in smaller
increments than normal.
6. Excessive effort is required to operate
the foot pump.
7. Platform won't lower when the release
pedal is pressed or lowers too slowly.
8. Platform lowers too quickly.
9. Platform lowers with a jerky motion.
Possible Causes:
A. No oil getting through the pump - not
enough oil in reservoir, or the pump
has become "air-locked."
B. Pinched or kinked hose.
C. Relief valve is opening.
D. Inlet check valve assembly being
held open by contamination.
A. Same as above.
B. Contamination holding open the relief
valve assembly.
C. Air in the pump piston.
A. Outlet check valve assembly being
held open by contamination.
A. Same as above.
A. Contamination holding open the relief
valve assembly or the inlet check
valve assembly.
A. Operating pressure is too high for
effective use at the current pump
displacement.
A. Pinched hose.
B. Release pin is bent or broken.
C. Velocity fuse is locked.
D. Flow control spool sticking or plugged
by contamination.
E. Object under platform or obstructing
the leg assembly movement or roller
travel.
F. Damaged to the leg assembly
structure.
A. Same as last item above.
A. Air in the hydraulic system, especially
the cylinder(s).
Action:
A. Check the reservoir's oil level. It
might be necessary to bleed air from
the pump piston at the socket-head
screw located on the left side of the
pump cylinder.
B. Visually inspect all hoses. Replace
or reposition as necessary.
C. Check for excessive load on the
platform.
D. Open the port on the left side of the
pump and clean any foreign material
from the ball and its seat. Press the
foot treadle to help flush any
contamination out of the port.
A. Same as above.
B. Open the port to the right of the
release pedal. Inspect and clean the
parts. Press the foot treadle to flush
contamination out of the port.
C. Bleed air from the piston.
A. Open the port on the left side of the
pump and clean any foreign material
from the ball and its seat.
A. Same as above.
A. Reference the instructions above for
cleaning each assembly.
A. Slide the speed selector forward to
put the pump into low volume
operation.
B. Check for excessive load on the
platform.
A. Check all hoses for kinks, crimped
spots, or visual damage. Reroute or
replace as necessary.
B. Inspect the release pin under the
release pedal. It should protrude
3/16", and should move in and out by
1/8"+.
C. Bleed air from the cylinder.
D. Remove the pressure hose to access
and inspect the flow control. Push on
the outside edge of the flow spool to
ensure it is fully pressed into the
cavity, and on the center to verify
that it moves freely.
E. Inspect for and remove any physical
obstructions.
F. Inspect for evidence of rubbing,
binding, twisting, etc. of the leg set.
A. Same as above.
A. Bleed air from the system at the
cylinder.
•The hydraulic fluid. The
system uses HO150
hydraulic fluid. Any anti-
wear hydraulic oil with a
viscosity grade of 150 SUS
at 100°F (ISO 32 @ 40°C)
such as AW 32 or non-
synthetic transmission fluid
is acceptable.